Motocross bikes epitomize the moto experience for many daring and adventurous riders. They are exhilarating and provide a sense of freedom as you cut through challenging terrain. Every motocross fan wants their own motocross bike. Many own several here in the US.
If you have the budget for a motocross bike, you want to get a machine that will give you the most value.
First, note that these bikes are designed to be raced on human-made tracks on natural terrains. Obstacles on these tracks include jumps, turns, berms, and intense sets of bumps or “whoops”. Therefore, they come with stiffer suspensions that can withstand high speeds, high jumps, rough terrain, and large impacts when landing.
Get ready for a smooth read as we review the top five best motocross bikes in the world that are on the market in 2021.
To begin with, here is a summarized table of these motocross bikes:
| Name | Engine | Cooling System | Fuel Tank Capacity | Ground Clearance |
| KTM SX 125 | 125cc | Liquid | 1.98 gal | 15.4 Inches |
| KTM 450 SX-F | 450cc | Air | 1.85 gal | 14.6 Inches |
| Suzuki RM-Z 250 | 250cc | Liquid | 1.7 gal | 13.6 Inches |
| Kawasaki KX250 | 250cc | Liquid | 1.3 gal | 13.2 Inches |
| Yamaha YZ250FX | 250cc | Liquid | 1.7 gal | 14.8 Inches |
KTM 125 SX
This KTM motocross bike might not be the most powerful KTM out there, but it’s the most technologically advanced in its class. The 125 SX has brought riders into dirt biking for decades and has a consistent record for producing world-class titleholders.
The bike is simple and effective, small enough with a 125cc two-stroke. It achieves its credibility by sporting a remarkable power-to-weight ratio.
Engine and Power
It runs on a 39.5 lbs. lightweight 125cc engine with impressive power across the rev range. The 125 SX features a 6-speed transmission and uses gas/oil.
Suspension
The 125SX hosts a unique suspension system. The WP AER 48 front fork, plus the rear WP shock system, provides a comfortable ride in the roughest terrains. This is unlike other 125s in the market that rely on cheaper parts.
Brakes
Twin-Disc Hydraulic Braking System
Price and Maintenance
The bike is small, reliable, and straightforward, requiring minimal maintenance. This is why we like this bike above other KTMs. Its Manufacturer’s Suggested Retail Price (MSRP) is $6,999.
KTM 450 SX-F
KTM continues to be a dominant force in motocross for their larger displacement bikes as well. The 450 SX-F’s revised ECU mapping and suspension settings for 2021 make it a competitive choice for this segment.
After nearly being overshadowed by KTM’s 350, the KTM 450 SX-F is enjoying significant dominance in recent years in both market popularity and race results. Earlier iterations of the Austrian maker’s motocross star fell short on suspension and low-end torque, but leaps in race development have sculpted the KTM 450 SX-F into a pure motocross sensation.
Engine and Power
KTM features a very lively 450cc engine, continuing the tradition for the 223-pound rocket. This machine delivers smooth, roll-on power that really shines as the other 2021 450’s wind down over 5800rpm. The Brembo hydraulic clutch is second to none, withstanding the rigors of abusive track conditions as well as any other.
Suspension
KTM retains its 2020 WP Xact AER 48 air fork, but it has been completely revamped and rebuilt internally for 2021. The bike has the same linkage and shock as last year as well, using a WP Xact shock adjustable for spring preload, high-/low-speed compression damping, and rebound damping.
Brakes
Up front, the 450 SX-F dawns a Brembo 2-piston caliper with 260mm brake disc. In back, the KTM comes equipped with a Brembo 1-piston caliper on a 220mm disc.
Price and Maintenance
The 2021 KTM 450 SX-F is competitive right out of the box, at $10,199. Maintenance matters when it comes to changing the oil, replacing/cleaning the filters, and checking the valves. Even then, this is a top shelf performance machine that is worth the fuss.
Suzuki RM-Z 250
This is another lucrative dirt bike that has produced worldwide champions in several AMA motocross championships. The Suzuki RM-Z 250 is a single-cylinder engine dirt bike with an ergonomic chassis designed for intense acrobatics and high-speed off-roading. Its configurations allow for high-impact jump landings and have an average fuel consumption.
Engine and Power
This Suzuki monster features a single-cylinder liquid-cooled 4-valve engine producing 250cc in displacement. The engine has a 13.8.1 compression ratio, surpassing most of the bikes in its caliber. The carburetion type is fuel-injected and uses a 5-speed manual transmission.
Suspension
Top-class bikes come with top-class specs and so does the RM-Z 250. The inverted front fork KYB suspension system is air-adjustable both for preload and rebounds damping. Its rear suspension is also from KYB and features a single spring adjustable preload plus a 13.6″ ground clearance.
Brakes
The front and rear brakes are Hydraulic style Discs.
Price and Maintenance
The sturdy aluminum frame is built for strength and durability. The hard ABS plastic body material holds up in the most challenging situations. Its base MSRP in the US is $7,899.
Kawasaki KX250
Kawasaki makes the ideal trail riding bikes you need. The KX250 has new advancements from the previous KX250 2020 model. Let’s see what it offers.
Engine and Power
This motocross bike comes with a single-cylinder 4-stroke 249cc liquid-cooled engine. These features deliver 40hp, enough to start the race at high speed and power and maintain it to the end. Its incredible power will need a stronger stopping force; that’s why it features a dual-piston caliper on the petal rear brake disk.
Suspension
The front suspension is a 48mm inverted spring telescopic coil fork with 23-position compression damping. The rear suspension is a dual-range 38-way rebound single spring with compression damping and a 12.4″ adjustable preload.
Brakes
Rear – 240mm single-piston caliber petal disc
Front – Semi-floating 270mm dual-piston petal disc
Price and Maintenance
The thin aluminum frame with forged lightweight plastics is durable lightweight, attractive, and well embedded. Maintenance is cheap, only demanding oil changes and garage checkups for overflows and loose parts. Get it at $8,299 in the US.
Yamaha YZ250F
Released in 2001 by Yamaha, this is among the best trail dirt bikes we have in 2021. The 4-stroke YZ250F was initially made of steel and aluminum, but the advanced model now consists of an all-aluminum body.
Engine and Power
This Yamaha combines the power of a 250cc bike and a 4-stroke feature for optimal control. Its high-power specs were complimented with a 2-gallon fuel tank that won’t run out on you. The single-cylinder engine is liquid-cooled and runs on a 6-speed gearbox.
Suspension
It features a speed-sensitive front inverted fork suspension system with an 11.8-inch adjustment level. The rear is a fully adjustable single shock with 12.0 inches of suspension travel.
Brakes
Front – Single 9.8″ disc
Rear – Single disc 9.6.”
Price and Maintenance
Other than the regular oil checks, leakages, and diagnosis for loose parts, the Yamaha YZ250F does not need much maintenance. Thanks to its durable all-aluminum construction. Its MSRP is $8,499.
In Conclusion
Motocross racing isn’t easy, nor is it cheap! Fast may not be free but identifying your focus for getting a bike is really the key. Are you racing? If so, you’re going to deal with a lot of maintenance and performance modifications. Are you trail riding? If you are, you’ll want to think about fuel mileage and maintenance intervals, more so than pure performance. Regardless of where your passion lies, there is a bike out there with your name on it.